线材显微组织对力学性能的影响

对A,B2个厂家生产的1100MPa级钢绞线用线材进行显微组织和力学性能检测,测得A厂线材索氏体片层间距平均为259.9nm,B厂为231.8nm;A厂线材奥氏体晶粒平均尺寸为12.89μm,B厂为19.22μm;用Hollomon关系式计算出线材加工的应力-应变关系。结果表明线材的屈服强度主要取决于索氏体片层间距,片层间距小的屈服强度大;抗拉强度与形变硬化指数有关,铁素体体积分数越高,形变硬化指数越高;索氏体片层间距越小,在相同变形量下变形分散在更多的层片条内,能承受的变形量就大,延伸率和断面收缩率就大。奥氏体晶粒尺寸与强度、塑性指标关系较小。

Effect of wire rod microstructure on mechanical properties

To check and measure the microstructure and mechanical properties of wire rod for 1 100 MPa grade stranded wire produced in A and B factory, the average slice distance of sorbite of wire rod produced in A and B factory are 259.9 nm and 231.8 nm respectively, the average austenite grains are 12.89μm and 19.22 μm respectively. The relationship between stress and strain in wire rod processing was calculated by Hollomon formula. The results indicate that the yield strength of wire rod mainly depend on slice distance, the yield strength is higher when slice distance is less; the tensile strength is relative to deforming hardening index, the sorbite volume fraction is higher, the deforming hardening index is higher; the sorbite slice distance is less, the deformation distribution to more slices at the same deformation quantity, it can bear more deformation, the elongation and the reduction of area are bigger. The austenite grains size is less relative to strength and plasticity index.